Cohesion tester for textile yarns



an- 16, 1962 A. PROMISLOW ETAL 3,015,743

COHESION TESTER FOR TEXTILE YARNS Filed May 22, 1959 I/Iflenfd/S K7 1? A. PROMASLOWJ, iii/5M 1444101444 ,3 [Jim-,4! 3- 4 @ezi 3,916,743 Patented Jan. 15, 1962 fine 3,016,743 COHESION FDR TEXTKLE Albert Louis Promislow, Qoilins Bay, Ontario, and Manrice Harold Waldrnan, St. Hilaire Station, Quebec,

Canada, assignors to Qanadian Industries Limited,

Montreal, Quebec, tlanada Filed May 22, 195"), Ser. No. 815,092 Claims priority, appiieatian Canada Nov. 25, 1958 2 Qiaims. (Ci. B -160) This invention relates to a method and apparatus for the measurement of cohesion between the individual filaments in a multi-filamentary textile yarn and more particularly to a method and apparatus for the measurement of this cohesion in synthetic yarns that have been treated with a finish.

In the handling of textile yarns, it is frequently desirable to treat the yarn with a finish, examples of processes in which finishes are used being spinning, weaving and tricot knitting. The purpose of a finish is threefold: it should act as an anti-static agent on the yarn, it should lubricate the yarn during subsequent passage through guides, and it should cause the filaments of the yarn to stick together. it is with the measurement of this latter property of cohesion that thisinvention is concerned. The invention is not, however, restricted to the measurement of cohesion in synthetic yarns treated with a finish, but may be applied to any multi-filamentary material wherein the filaments are not twisted tightly together.

The cohesion of the filaments in a textile yarn is an important property of that yarn, and determines the ease with which it can be woven into cloth, and the appearance and properties of that cloth after weaving. In addition, the effectiveness of a finish may in part be determined by its effect on cohesion.

It is an object of this invention to provide a method and apparatus for measuring the cohesion of filaments in a multi-filamentary yarn. A further object is to provide a means of measuring, in part the effectiveness of finishes on textile yarns.

Additional objects will appear hereinafter.

The apparatus of this invention comprises essentially, in combination, an electrically grounded cup-shaped metallic container, an insulating lid for said container, an electrode passing centrally through said lid and having at its lower end retaining means for at least one sample of a multi-filamentary yarn, and means for supplying an adjustable measurable high voltage to said electrode.

The apparatus may conveniently have one or more transparent windows in the cup-shaped container so that the yarn samples may be illuminated and observed during measurement.

The invention will be more fully illustrated by reference to the accompanying drawing wherein FIG. 1 is a side elevation of one form of the apparatus of the invention and FIG. 2 is a more detailed view of the electrode with samples attached thereto.

In FIG. 1, the grounded container 1 is shown with transparent windows 2 and 3 and a lid 4 sitting on a rubber gasket 5. The electrode 6 is connected to the variable DC. voltage source 14 by means of a metallic coupler 7 and cables 3 and 9 having an insulating shield 10. The applied voltage is measured by voltmeter 13. In FIG. 2 multi-filamentary yarn samples 11 are tightly clamped to the electrode 6 as at 12.

In the method of operating the apparatus of this invention a number of samples of yarn are taken from the spool of yarn on which the data on cohesion are required. The number of samples is suitably ten and the length of each one is suitably one inch, although the larger the number of samples the more meaningful the result will be. These samples 11 are attached to the electrode 6 as at 12 without being touched by hand, and the end of each sample remote from the electrode is moistened with a small quantity of quiclcsetting glue. The electrode is then passed through the lid and the apparatus assembled.

On applying an increased voltage to the electrode, the samples are observed to dilate as individual filaments overcome their cohesion and repel each other. The voltage at which each yarn sample first appears to dilate is noted, and the average taken for all samples of one yarn. The resulting voltage is a direct measure of the cohesion of the filaments in the yarn.

The apparatus is suitable for all multi-filamentary yarns, and the effect of some trial finishes will be illus trated by the following results on polyethylene terephthalate yarn.

It is necessary that some small conductivity be present in the yarn. Thus certain synthetic yarns cannot be tested in the apparatus of this invention unless treated with a small amount of finish, for the voltage will not distribute itself over the yarn. For materials of poor conductivity, a pause must be made between each voltage increment to allow the voltage to distribute itself.

Furthermore, in order to reduce the danger of sparkover or undesirable induction eflfects, it is preferable that the cup-shaped container should be of such a size as to have a gap of about 3" between said container and the samples to be tested.

It can be seen that the method and apparatus of this invention have broad applications and are only to be limited by the following claims.

What we claim is:

1. An apparatus for measuring the cohesion of the filaments in a multi-filamentary textile yarn which comprises essentially, in combination, an electrically grounded cup-shaped metallic container having at: least one transparent window in the side wall thereof, an insulating lid for said container, an electrode passing centrally through said lid and having at its lower and retaining means for at least one sample of said textile yarn, and means for supplying an adjustable measurable high voltage to said electrode.

2. A method of measuring the cohesion of the filaments in a multi-filamentary yarn which comprises suspending in the atmosphere a multiplicity of freely hanging samples of said yarn from an electrode, supplying a voltage to the samples through said electrode, slowly increasing said voltage, observing the dilation of at least one filament from the remainder of at least one yarn sample, and measuring the voltage supplied when said dilation occurs.

References Cited in the tile of this patent UNITED STATES PATENTS 1,922,933 Dirks Aug. 15, 1933 FOREIGN PATENTS 165,275 Switzerland Jan. 16, 1934 OTHER REFERENCES Publication, A Textbook of Physics by Spinney, The Macmillan Co., 1921, page 279. (Copy in Div. 36.) 

1. AN APPARATUS FOR MEASURING THE COHESION OF THE FILAMENTS IN A MULTI-FILAMENTARY TEXTILE YARN WHICH COMPRISES ESSENTIALLY, IN COMBINATION, AN ELECTRICALLY GROUNDED CUP-SHAPED METALLIC CONTAINER HAVING AT LEAST ONE TRANSPARENT WINDOW IN THE SIDE WALL THEREOF, ANINSULATING LID FOR SAID CONTAINER, AN ELECTRODE PASSING CENTRALLY THROUGH SAID LID AND HAVING AT ITS LOWER END RETAINING MEANS FOR AT LEAST ONE SAMPLE OF SAID TEXTILE YARN, AND MEANS FOR SUPPLYING AN ADJUSTABLE MEASURABLE HIGH VOLTAGE TO SAID ELECTRODE. 